A simplified iteration technique for designing galvanic cathodic protection of metalworks

A simplified iteration technique for designing galvanic cathodic protection, which is sufficiently general, easy, and free from crude errors, is suggested. A required accuracy of calculations is promptly reached since it cannot exceed the accuracy of the preset starting parameters. The descriptiveness of the method makes it useful in training young specialists and students. Several particular solutions are based on an assumption that the polarization resistances of both the anode and the protected structure are independent of current density. This assumption makes the protection current independent of the polarization resistance of the structure and determined by the anode's characteristics, the structure's potential, and the conductivity of the corrosive medium

Fullerene-mediated electrosynthesis of Ag–C<inf>60</inf>nanocomposite in a water-organic two-phase system

© 2017 By example of fullerene-mediated electrosynthesis of Ag–C 60 nanocomposite in water–o-dichlorobenzene, the possibility of using a liquid–liquid two-phase system for the electro- synthesis of metal nanoparticles has been demonstrated for the first time

Synthesis, structure, and antimicrobial activity of (carboxyalkyl)dimethylsulfonium halides

© 2017, Pleiades Publishing, Ltd. Reactions of a series of ω-halocarboxylic acids (2-bromo-, 2-chloroethanoic, 3-bromo- and 3-chloropropanoic) with dimethyl sulfide resulted in the formation of stable (carboxylalkyl)dimethylsulfonium bromides and chlorides. Composition and structure of the salts obtained were established by a complex of chemical, physical and physicochemical methods. The sulfonium salts obtained showed high antibacterial and antimycotic activities with respect to the pathogenic microflora of humans and animals

First coordination polymer based on diterpenoids. Synthesis, structure, and magnetic properties

© 2017, Springer Science+Business Media, LLC. One-dimensional coordination polymer was obtained by cation exchange reaction of triethylammonium salt of methyl ent-16α-H-phosphonyloxybeyeran-19-oate with CuCl 2 . Its structure was determined by single crystal X-ray diffraction analysis. The formation of hydrophilic channels consisting of phosphorus containing fragments, copper atoms, and water, which are framed by hydrophobic surroundings from tetracyclic bulky beyeran substituents, is observed in the crystal. The study of the temperature dependence of the static magnetic susceptibility of the polymer indicates a weak antiferromagnetic interaction between the copper spins

Electron Transfer and Unusual Chemical Transformations of F4-TCNQ in a Reaction with Mn-Phthalocyanine

© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim The interaction of manganese phthalocyanine with F4-TCNQ is accompanied by the transformation of the acceptor molecule into a new organic ligand, the 4-(dicyanomethanido)tetra-fluorobenzoate dianion, resulting in the formation of a unique MnIII charge-transfer complex, in which two Mn phthalocyanine moieties are bridged by the dianion, with parallel arrangement of all aromatic fragments and an interplanar distance of 3.30 Å. The formation of the complex takes place in a 2:1 ratio, with the two electrons transferring from two donor molecules to an acceptor molecule. Magnetic measurements reveal that MnIII ions in the studied complex occur in the high-spin state S = 2 and are coupled antiferromagnetically, presumably by the superexchange mechanism through the 4-(dicyanomethanido)tetrafluorobenzoate dianion bridge, with an interaction constant of J = 5 cm–1 (7 K). According to the electrochemical data, the new complex appears to have unusual redox properties and might be described as an electronic reservoir with strong acceptor ability, being able to take seven electrons. Notably, all of the reduction–oxidation steps are reversible, proceeding without structural changes

Synthesis and structure of novel phosphorylated azomethines

© 2016 Taylor & Francis Group, LLC.The condensation of do-, hexa-, octadecan-1-amines with bromo- and nitrobenzaldehydes yielded a series of Schiff bases in good yields. Subsequent reaction of these compounds with dioctylphosphine oxide yielded phosphorylated azomethines and some were characterized using X-ray crystallography. The structure of the isolated compounds was determined by IR and NMR spectroscopy, elemental analysis, and their thermal stability was studied by simultaneous thermogravimetry and differential scanning calorimetry. All of the synthesized compounds were tested for their antibacterial and anti-Candida activity. A number of the compounds exhibited antimicrobial activity comparable to that of the commercially available drugs, ciprofloxacin and clotrimazole

Observation of an Excited Bc+ State

Using pp collision data corresponding to an integrated luminosity of 8.5 fb-1 recorded by the LHCb experiment at center-of-mass energies of s=7, 8, and 13 TeV, the observation of an excited Bc+ state in the Bc+π+π- invariant-mass spectrum is reported. The observed peak has a mass of 6841.2±0.6(stat)±0.1(syst)±0.8(Bc+) MeV/c2, where the last uncertainty is due to the limited knowledge of the Bc+ mass. It is consistent with expectations of the Bc∗(2S31)+ state reconstructed without the low-energy photon from the Bc∗(1S31)+→Bc+γ decay following Bc∗(2S31)+→Bc∗(1S31)+π+π-. A second state is seen with a global (local) statistical significance of 2.2σ (3.2σ) and a mass of 6872.1±1.3(stat)±0.1(syst)±0.8(Bc+) MeV/c2, and is consistent with the Bc(2S10)+ state. These mass measurements are the most precise to date

Studies of η\eta and η′\eta' production in pppp and ppPb collisions

The production of $\eta$ and $\eta'$ mesons is studied in proton-proton and proton-lead collisions collected with the LHCb detector. Proton-proton collisions are studied at center-of-mass energies of $5.02$ and $13~{\rm TeV}$, and proton-lead collisions are studied at a center-of-mass energy per nucleon of $8.16~{\rm TeV}$. The studies are performed in center-of-mass rapidity regions $2.5<y_{\rm c.m.}<3.5$ (forward rapidity) and $-4.0<y_{\rm c.m.}<-3.0$ (backward rapidity) defined relative to the proton beam direction. The $\eta$ and $\eta'$ production cross sections are measured differentially as a function of transverse momentum for $1.5<p_{\rm T}<10~{\rm GeV}$ and $3<p_{\rm T}<10~{\rm GeV}$, respectively. The differential cross sections are used to calculate nuclear modification factors. The nuclear modification factors for $\eta$ and $\eta'$ mesons agree at both forward and backward rapidity, showing no significant evidence of mass dependence. The differential cross sections of $\eta$ mesons are also used to calculate $\eta/\pi^0$ cross section ratios, which show evidence of a deviation from the world average. These studies offer new constraints on mass-dependent nuclear effects in heavy-ion collisions, as well as $\eta$ and $\eta'$ meson fragmentation.Comment: All figures and tables, along with machine-readable versions and any supplementary material and additional information, are available at https://lhcbproject.web.cern.ch/Publications/p/LHCb-PAPER-2023-030.html (LHCb public pages

Search for CP\textit{CP} violation in the phase space of D0→KS0K±π∓D^{0} \rightarrow K_{S}^{0} K^{\pm} \pi^{\mp} decays with the energy test

A search for $\textit{CP}$ violation in $D^{0} \rightarrow K_{S}^{0} K^{+} \pi^{-}$ and $D^{0} \rightarrow K_{S}^{0} K^{-} \pi^{+}$ decays is reported. The search is performed using an unbinned model-independent method known as the energy test that probes local $\textit{CP}$ violation in the phase space of the decays. The data analysed correspond to an integrated luminosity of $5.4~$fb$^{-1}$ collected in proton-proton collisions by the LHCb experiment at a centre-of-mass energy of $\sqrt{s}=13$~TeV, amounting to approximately 950000 and 620000 signal candidates for the $D^{0} \rightarrow K_{S}^{0} K^{-} \pi^{+}$ and $D^{0} \rightarrow K_{S}^{0} K^{+} \pi^{-}$ modes, respectively. The method is validated using $D^{0} \rightarrow K^{-} \pi^{+} \pi^{-} \pi^{+}$ and $D^{0} \rightarrow K_{S}^{0} \pi^{+} \pi^{-}$ decays, where $\textit{CP}$-violating effects are expected to be negligible, and using background-enhanced regions of the signal decays. The results are consistent with $\textit{CP}$ symmetry in both the $D^{0} \rightarrow K_{S}^{0} K^{-} \pi^{+}$ and the $D^{0} \rightarrow K_{S}^{0} K^{+} \pi^{-}$ decays, with $p$-values for the hypothesis of no $\textit{CP}$ violation of 70% and 66%, respectively.Comment: All figures and tables, along with any supplementary material and additional information, are available at https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2023-019.html (LHCb public pages

Fraction of χc\chi_c decays in prompt J/ψJ/\psi production measured in pPb collisions at sNN=8.16\sqrt{s_{NN}}=8.16 TeV

The fraction of $\chi_{c1}$ and $\chi_{c2}$ decays in the prompt $J/\psi$ yield, $F_{\chi c}=\sigma_{\chi_c \to J/\psi}/\sigma_{J/\psi}$, is measured by the LHCb detector in pPb collisions at $\sqrt{s_{NN}}=8.16$ TeV. The study covers the forward ($1.5<y^*<4.0$) and backward ($-5.0<y^*<-2.5$) rapidity regions, where $y^*$ is the $J/\psi$ rapidity in the nucleon-nucleon center-of-mass system. Forward and backward rapidity samples correspond to integrated luminosities of 13.6 $\pm$ 0.3 nb$^{-1}$ and 20.8 $\pm$ 0.5 nb$^{-1}$, respectively. The result is presented as a function of the $J/\psi$ transverse momentum $p_{T,J/\psi}$ in the range 1$<p_{T, J/\psi}<20$ GeV/$c$. The $F_{\chi c}$ fraction at forward rapidity is compatible with the LHCb measurement performed in $pp$ collisions at $\sqrt{s}=7$ TeV, whereas the result at backward rapidity is 2.4 $\sigma$ larger than in the forward region for $1<p_{T, J/\psi}<3$ GeV/$c$. The increase of $F_{\chi c}$ at low $p_{T, J/\psi}$ at backward rapidity is compatible with the suppression of the $\psi$(2S) contribution to the prompt $J/\psi$ yield. The lack of in-medium dissociation of $\chi_c$ states observed in this study sets an upper limit of 180 MeV on the free energy available in these pPb collisions to dissociate or inhibit charmonium state formation.Comment: All figures and tables, along with machine-readable versions and any supplementary material and additional information, are available at https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2023-028.html (LHCb public pages